Dear Mr Dore,

The services you provide are important for establishing a new process or
changing an old one, but not really feasible for process control.  For
example, the flux corrosivity test is generally used if a manufacturer is
considering a change to a different flux.  It can be used as a receiving
quality control tool, but unless the user has had problems with the vendor
in the past, I would not worry about it.  As you know, SIR,
electromigration, and microsectioning is not a real "quick" test.  Using
these tests as a process control tool would take too long and by the time
the test results showed a problem, too much product has been built.  Ionic
contamination testing is a good process control tool if it is done in house.
By the time the parts are packaged, shipped, received, tested, analysis sent
and received by the manufacturing engineer, the process may have shifted two
or three times.  In addition to being good tests for establishing new
processes, they are also good failure analysis troubleshooting tools.  That
is why you have experienced that your service is required by Process
Engineers and Manufacturing Engineers who wait for the problem to arise on
their PCB assembly.

Tim Crawford
EMPF


>>
>>At 12:38 4/23/96 GMT, Maurice Dore * wrote:
>>>
>>>
>>>If I can have a moment of your time, I would like to ask for your opinion on
>>>materials analysis in electronics manufacturing.
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